Ok so I've had this car for about 2 months now. I replaced the alternator, rotors, drums, brake pads and shoes. But I noticed about a weeks ago that my temp gauge was flip flopping from normal to hot from normal to hot quickly. There wasn't any antifreeze in it and only water. I bleed it and refilled it and it was working right again, about 3 days later I checked to see if the reserve was still full, and it was. About a week later the gauge started acting up again. It does not seem like the engine it overheating. I checked to see if there was antifreeze in it and the reserve and radiator where completely empty. I filled it back up and it was good for about a week. Today I got into the car and turned the heat on. Mind you it was about 35 degrees out this morning. So I started driving and I noticed that the heat was not getting hot. Within a few seconds the gauge started going up and down again. I popped the hood and checked the reserve and it was just as full as the day I filled it. I waited about 20 minutes took off the radiator cap and filled that with antifreeze. It took about 1/4 of the gallon. Got in the car started it up and it was good again. WHAT IS THE PROBLEM? I am going to replace the thermostat on the weekend when I have the time. I checked the oil to make sure the antifreeze wasn't disappearing into the engine but it looks good. I changed the oil the day I bought the car. I don't see any leaks in the hoses but I could be missing something. HELP ME PLEASE!!!

Also the car stalls every once in a while. If I am sitting at a red light for a while and then let up on the brake and hit the gas hard it seems to hesitate and sometimes it stalls all together. I used some seafoam I put half a can in the vacuum port and the other half in the gas tank. The car runs great an there is no check engine light on. Any suggestions are appreciated!

 

You're obviously losing coolant somewhere if you have to keep adding it. Not really sure if your thermostat would be the issue there, unless somehow/someway you see coolant leaking underneath the thermostat, which would then only be the gasket since you mentioned no over heating. Have you checked everywhere for a coolant leak? And are you getting any smoke out of your exhaust? I'm also going to say that part of your problem could be your temp gauge. Sounds like there are a few issues with your cooling system, not just your gauge.

 

I don't see any leaks i was thinking about getting it pressure tested .. Maybe some white smoke from the exhaust when the car starts. Last time I looked the reserve was full, but i did put some coolant into the radiator and got about 1/4 of the gallon into it. If the head gasket is blown would the engine be overheating all the time, or would there definitely be coolant in the oil?

 

Not all bad head gaskets mix the water with the oil. But I would test for hydrocarbons. Make sure your cooling fans are coming on and shutting off normally. Double and triple check any coolant leaks. A lot of times it can be somewhere just above your exhaust and you wont see any signs of leaks because the exhaust is hot.

As said above, it could also be your Temp Sending Unit/Gauge Sending Unit.

 

Ok so first thing is I'm going to pressure test it. I'll post the outcome tomorrow afternoon... I'm hoping its a leak and not the head gasket!

 

Check the small coolant lines that go to the IACV.

 

could be the head gasket. my car would overheat but not all the time. sometimes i could drive it and it would be fine and other times it would overheat. turned out the head gasket was bad but it was not leaking antifreeze, it was actually sucking in air through the head gasket and creating air bubbles in cooling system. but if you are losing antifreeze it might not be head gasket. your best bet would be to pressure test it. let us know how it goes

 

OK so I drove the car for another day after I wrote my last post on 11/9 so on 11/10 I drove it about for about 15 mins. When I would put the car in gear it was idling really rough then while I was driving it when I would come to a stop it would either hesitate or stall completely. The night before this I checked the coolant and bleed the coolant lines for air. It never completely was a straight flow of coolant so I knew that somehow there was air getting into the coolant line. Well like I said I drove it the next day and it was smoking pretty bad from the exhaust and it was idling rough. I got to a parking lot and stopped for a few and I notice that when I would start the car that all the coolant I had just put into the radiator would blow out through the reserve. Got in it to go home and it would not stay on it would idle rough and stall at every stop. If I hit the gas it was pathetic it would not move! Got home called the shop and he came towed it and and 15 mins later called to confirm that it was the head gasket that it had failed every test. He said he was going to send the head out to the machine shop to make sure it wasn't warped and let me know. Called three days later said everything was good with the head and they would have it back together and ready the next night. He ended up calling me back and said that my radiator had a crack in it ... that may have caused the head gasket to blow. New Radiator, new head gasket, and new timing belt. Runs like its brand new =] I think the people who sold it to me put some head gasket sealant or something in it and when I got it home after buying it we ran Sea-foam threw it and cleaned it all out. Ehh you live and you learn. I still love the car! But thanks everyone for the tips its much appreciated!